Art or process of controlling the burning of time-powder trains



May 1, 1923.

A. S. MILLER ART OR PROCESS OF CONTROLLING THE BURNING OF TIME POWDE TRAINS Filed Sept. 28, 1917 H 2 P 2 v i atenterl may t, 35923,

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AL'IEN S. MILLER, 0F BALTIMORE, MARYLAND.

ART OR PROCESS OF CONTROLLING THE BURNING OF TIME-POWDER TRAINS Application filed September 28, 1917.

T0 aZZ whom it may concern:

Be it known that I, ALTEN S. MILLER, a citizen of the United States, residing at Baltimore city, in the State of Maryland, have invented certain new and useful Improvements in the Art or Processes of Controlling the Burning of Time-Powder Trains, of which the following is a specifi cation.

This invention relates to theart or process of controlling the burning operation of'time powder trains.-

Heretofore the accuracy in the time of burning of time powder trains in fuses has depended on the uniformity of the atmospheric pressures to which the burning powder train has been subject during its burning operation, with the result that the time of operation has varied with the surrounding atmospheric pressures. These inaccuracies are multiplied if the fuses are employed in mountainous regions or in high altitudes, and the operations desired are frequently delayed until comparatively long periods after the time the fuse has been set to operate with the result that they are ineffective of the desired result.

These inaccuracies in the burning of time fuses are due to the fact thatthe higher the altitude in which the fuse is used the less will be the atmospheric pressure under which the powder-train must burn, and theslower will the burning be. Consequently, in the case of a shell for example, if the time rings are adjusted to effect an explosion at a given time, and the shell is then fired into the air to a considerable altitude, the higher the shell is projected, the slower will the powder train burn, and the explosion, in the case of a shell, will not take place at the end of the predetermined number of seconds indicated by the time rings.

By means of my method of control, I overcome theseserious objections, in that I maintain a substantially uniform internal pressure on the burning powder-train, irrespective ofthe external'atmospheric pressures, with the result that the operation to be produced by the burning powder train, will take place atthe time desired.

One object therefore of my present invention is to provide an operation in the fuse and on the powder-train that will cause the powder-train to burn at-an approximately uniform rate of speed, irrespective of a wide Serial No. 193,691.

range of variationsin externalat'mospheric pressures.

Another object is toproduce a conditionin the fuse that willmaintain a practicallyuniform internal pressure on the burning time powder-train, and thereby avoid' var'iations in the time of burning that follows variations in pressure.

A further object of the present invention is to produce an approximately predetermined pressure on the burning powder-train and maintain that pressure by allowing'the escape of gases that would create an excess pressure. p

A still further object of the invention is to control the escape of gas pressure that is generated in a time fuse during the burning of thepow-der-train, by av pressure that is stored in the fuse whereby-to maintain an approximate uniform pressure on the burnT ing train and effect the operation at the time desired.

The means employed in carrying outthe process and maintainingthe pressure conditions-in the fuse, may vary, but for, the purpose of illustration, I have shown in'the accompanying drawing a longitudinal section through a shell with a fuse. structure located? therein having means for efiecting the operations and maintaining the pressures desired.

Referring to the drawing the numeral 5, designates a shell casing of the shrapnel type, provided at the forward end with av suitableplug 6,. which latter. is provided with a chamber 7 and which also haspassages 8, leadingtherefrom, which passages communicate withv the time-powder-train grooves 9 and 10 in the time-rings l1 and'l2 respectively.

A suitable plunger device 13, is located at the outer end of the plug 6,]by meansflof which, and upon the shock of firing, ignition of the powder-train in the groove 101will take place to start the timing operation.

The devices-above referred to are old; in the art but are maintained in a, fuse, operated in accordance with my present inven:

Beyond the, plug 6, the fuse portion oflthe shell has a so-called metal cap 14,-with channels 15 extending therethrough. The inner ends of these channels communicate with'the time-train grooves in the time rings wherebytion and thereforeare only briefly referred to vent the latter of gases generated by the burning powder-train while the shell is in flight,the gases passing through vent apertures 16, that are provided in the nose 17, of the shell.

Various means may be employed in the fuse to maintain a uniform internal pressure on the powder train, as will be seen from the present disclosures, but in the form of structure disclosed I interpose a valve device between the vent channels 15, and the external vent apertures 16, which valve will. remain seated until a predetermined pressure on the channel side is reached, whereupon the valve will unseat and allow gas to escape and so prevent an excess pressure in the channels and on the time train.

In the form of structure disclosed I provide a cavity 18, in which the outer ends of the channels 15, terminate, and the outlet from said cavity is controlled by a valve structure 19.

In the present instance the valve 19, has the form of a puppet valve in that it has an annular flange 20, that seats around the cavity 18, and is guided in its movement toward or from the seat by guide pins 21, which prevent lateral displacement of the valve during the shock of firing or while the projectile in which the fuse is located is in flight. The valve, in this instance, is of a conical form with its apex projecting to ward the nose-end of the shell.

The nose-end of the shell is provided with a conical casing 17, the interior base-end of which is rigidly attached to an internallythreaded bushing 22, that has threaded engagement with the cap 14:.

On the interior of the nose casing 17, I provide a pressure receptacle 23, which, in this instance, has the form of a dome whereby to produce a chamber 24:, for a purpose presently to be explained. This pressure receptacle, in this instance, has an annular flange 25, around the base of the dome, which flange is provided with a plurality of ports 26, and the extreme end portion 27, of the flange is formed into a ring-shape and has threaded engagement with the bushing 22, whereby to secure the same in an encircling position with respect to the valve 19. A pin, 33 looks the parts together.

The purpose of the pressure receptacle is to provide means for exerting a predetermined pressure on the upper side of the valve 19, whereby to keep the valve yieldingly pressed to its seat, but which will permit the valve to unseat when the pressure on the lower side exceeds that on the upper side, and in this way will maintain a substantial equalization of pressures on the opposite sides of the valve during the burning of the powder train.

In the present instance, the means employedin the pressure receptacle to transmit the desired pressure, is a diaphragm 28, which extends across the base of the dome and closes the bottom of the dome-chamber 24:, and on the upper side of this diaphragm and confined in the chamber, in this instance, is a fluid, such as air or gas. This fluidpressure in the dome-chamber exerts a constant predetermined pressure on the upper side of the diaphragm and keeps the latter pressed down on top of the valve 19, whereby to normally keep the valve seated over the chamber 18, and the outer ends oi the vent-channels 15. Of course, in practice, the relative areas of the valve and diaphragm are such that no matter what the atmospheric pressure on the exterior of the shell or on the interior of the nose casing 17 and fuse may be, the valve 19, will be kept seated by the pressure exerted by the pressure means in the chamber 2 1, until the pressure in chamber 18, and passages 15, overcomes that in chamber 24, at which moment valve 19, will unseat and allow the excess pressure from the channels and on the time powder train to vent.

By this means a practically uniform pressure will be maintained in the fuse on the time powder-train regardless of the atmosphericpressures on the exterior of the shell and on the interior of the nose casing 17, and on the fuse, consequently the time powdertrain will burn at a uniform speed in the fuse no matter what the altitude or the exterior barometric pressures may be.

From the foregoing explanation of the structure, it is to be understood that when the fuse is ignited, the gases generated by the burning powder will be cut off from escaping as long as valve 19, is held closed by the fluid pressure in the dome chamber, but when the pressure on the fuse side of the valve builds up to a point that will enable it to lift the valve against the stored-up pressure on top, then the excess pressure will vent by passing under the valve and out through ports 26 and 16, to the atmosphere.

It will thus be seen that by means of my process the external atmospheric pressure will no longer determine the pressure on the burning train, and that the pressure on the train will be determined by the pressure carried in the fuse independently of the atmospheric pressure.

By means of the improved method I am able to maintain a practically uniform pressure on the powder train during burning and I therefore gain a greater accuracy in the time of operation irrespective of the barometric pressures to which the fuse is subject during operation.

Having described my invention, what I claim is,-

1. The method of controlling the burning of time powder trains in fuses, consisting in igniting the powder train, confining the gases generated by the burning powder train by a valve that is held closed by pressure stored in the shell and maintaining the closing-pressure on said valve irrespective of the external atmospheric pressures.

2. The method of controlling the burning of time powder trains in fuses, consisting in igniting the powder train, providing a stored-pressure actuating-device in the shell, interposing a valve structure between the stored pressure actuating device and the powder train, providing a vent to the atmosphere and providing balancing areas on the valve structure and the stored-pressure actuating-device which balanced areas are subject to atmosphere pressure.

3. The method of controlling the burning of time powder trains in fuses, consisting in providing a valved escape from the powder train, seating said valve by a device that is held in position by a stored-up pressure in the shell, providing said valve and said device with areas that substantially balance, and forming a vent from the opposing balanced areas of said device and valve to the atmosphere whereby to maintain an approximately uniform pressure on the valve irrespective of external atmospheric pressures.

4. The method of controlling the burning I of time powder trains in fuses, consisting in igniting the powder trains, providing an actuating device in the shell which is held by stored-up pressure carried in the shell, locating a valve between the actuating device and the time powder train,-the actuating device and the valve having areas that balance and are subject to atmospheric pressure the valve being seated by the stored-up pressure and the actuating device being actuated by the gases generated by the powder train while the atmospheric pressure on the actuating device and the valve are equal.

5. The method of controlling the burning of time powder trains in fuses, consisting in igniting a powder train, carrying a predeterminal pressure in the fuse that is sepa-' rate and independent of the exterior atmospheric pressure and utilizing the carried pressure to determine the pressure of the gases to be maintained on the powder train and venting only the generated gas pressure in excess of the carried pressure.

In testimony whereof I afiix my signature in the presence of two witnesses.

ALTEN S. MILLER. Witnesses:

ADDISON O. ARMSTRONG, SYLVESTER A. SPERLING. 

